Sludge Drying with Solar and Renewable Energy

The HUBER Solar-Regenerative Sludge Dryer SRT is able to meet the most different specific customer requirements, whether as a pure solar dryer or all-year-round dryer operated with additional heat. Also the automation degree of sewage sludge feeding and removal is variable.

The combined sludge turning and transporting system is at the heart of the drying plant. The sludge is transported through the hall virtually continuously or as an option in batches. With its double shovel the turning/transporting unit can not only aerate, break up and move the sludge through continuous shovelling but also achieve a controlled distribution of sludge in its shovels. Due to the latter function of the shovel sludge can be back-mixed or sludge feeding and removal take place at the same hall side.


The dryer consists of a transparent thermo shell in which the HUBER Sludge Turner SOLSTICE® distributes the sludge all over the area. The air and sludge bed are heated by solar radiation. In addition heat (for example at 50° C) can be added via floor heating. Heat input via heating coils is also possible (usually with temperatures above 70° C). External heating can be operated with exhaust heat from a block heat and power plant or by means of a heat pump which uses the heat contained within wastewater (WWTP effluent).
(See also HUBER Solution Sludge Drying with Wastewater Heat)

If an additional external heat is used, space requirements are smaller compared to pure solar drying and plant operation is possible all year round even in areas offering only moderate or rare solar radiation.